Bizarre Features of Saturn's Radio Emissions

Saturn is a source of intense radio emissions. The radio waves are
closely related to the auroras near the poles of the planet. These auroras
are similar to Earth's northern and southern lights. The
Cassini spacecraft began detecting
these radio emissions in April 2002 when Cassini was 2.5 astronomical units
from the planet using the
Cassini Radio and
Plasma Wave Science (RPWS) instrument. The RPWS has now provided the
first high resolution observations of these emissions that show an amazing
array of variations in frequency and time. In this example, it appears
as though the three rising tones are launched from the more slowly varying
narrowband emission near the bottom of this display. If this is the case,
it represents a very complicated interaction between waves in Saturn's
radio source region, but one which has also been observed at Earth!

The sound of the radio emissions can be heard by clicking on the "Play
Audio" button or by selecting the video version which includes an animated
cursor that indicates the time corresponding to the audio track. Time
on this recording has been compressed such that 13 seconds corresponds to
27 seconds, or, about 2x real time. Since the frequencies of these emissions
are well above the audio frequency range, we have shifted them downward by a
factor of 260.